Fix coverity 1212409 by using std::vector.

Update int array that was not initialized in reachingDefinitionsAnalysis.cpp to
simply be a std::vector<int>. std::vector will take care of the initialization,
and coverity should be happy.
Merge branch 'master' of https://github.com/chapel-lang/chapel into coverity-1212409
Remove localDefs init loop. std::vector does this already.
Merge pull request #872 from thomasvandoren/coverity-1212409

Fix coverity 1212409 by using std::vector.

Update int array that was not initialized in reachingDefinitionsAnalysis.cpp to
simply be a std::vector<int>. std::vector will take care of the initialization,
and coverity should be happy.

r: @vasslitvinov